Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=false, idempotentHint=false and destructiveHint=false, so the mutation profile is known. The description adds nothing beyond them — notably it does not warn that repeated invocation creates duplicate budgets (non-idempotent), nor what validation or permissions apply.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

It is brief, but brevity here is under-specification rather than conciseness — there is only one sentence and it duplicates the name. No information is front-loaded because no information exists.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a create tool with five undocumented parameters, no output schema, and non-idempotent behavior, this description leaves an agent unable to construct a correct call beyond the single required field. Annotations cover safety but not the substantive gaps.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0% across 5 parameters, so the schema carries no semantic detail and the description supplies none. Fields like alert_at_pct, is_active, and monthly_limit_cents are completely unexplained in both places.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description restates the tool name with no added specificity: 'Create a expense_budget.' It does name a verb and resource, but offers nothing to distinguish it from siblings like expense_budget_update or expense_budget_list beyond the obvious create verb.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No when-to-use guidance, no prerequisites, no mention of alternatives such as expense_budget_update for modifying an existing budget. The agent must infer everything from the service-prefixed name.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.